Daily Updates: January |
S |
M |
T |
W |
T |
F |
S |
23 |
24 |
25 |
26 |
27 |
28 |
29 |
30 |
31 |
|
|
|
|
|
Daily Updates: February |
S |
M |
T |
W |
T |
F |
S |
|
|
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
TODAY'S WEATHER
Broken
Clouds
78°F (25.6°C)
Latitude:
9 deg 37 N
Longitude: 104 deg 15W
Wind Direction: NE
Wind Speed: 16 Knots
Sea
State: 3Swell(s)
Height: 9 Feet
Sea
Temperature: 82°F (27.8°C)
Barometric
Pressure: 1011.5 MB
Visibility: 15 Nautical Miles
Breakfast
Scrambled eggs
Cheese, onions, and pepper quesadillas
Fresh fruit
Potatoes with onions
Pancakes
Lunch
French fries
Italian subs
Cole slaw
Salad bar
Pasta salad
Asparagus soup
Snickers ice cream bars
Dinner
Strip sirloin steak
Garlic red potatoes
Tofu stir-fry
Shrimp stir-fry
Salad Bar
Chocolate cake with raspberry layers
Vanilla ice cream
After his last dive in Alvin, Dave Olds
gets a helping hand into the pool.
Daily Update: Dive 3529
February 4, 2000
By Dr. Dan Fornari and Sam Dean
Todays sunrise was a study in grays and
peach colors, and streaks of white clouds high in the sky. Our
gazing at the dawn was interrupted as we pulled the Towed Camera
Sled up over the side of RV Atlantis at 0630 hours. When
it was on deck we noticed there was a problem - one of the battery
boxes had its rubber bladder bulging out like a balloon ready
to burst! Each battery box contains oil, not too much different
from cooking oil, which protects the electrical connections and
the gel in the battery from the harmful effects of seawater.
It turns out that some seawater (almost 2 gallons!) had seeped
into the casing, forming an oil-water emulsion, or what some
chemists call a mousse (like the texture of chocolate
mousse - but you cant eat this stuff!).
An emulsion is created when two immiscible (not able to be mixed)
liquids are forced together, causing one of the liquids to break
up into tiny droplets held in suspension within the other liquid.
Some common emulsions you use every day include oil and vinegar
salad dressing, milk, and mayonnaise.
The bladder was bulging because the seawater had reacted with
the gel of the battery and made gas. Greg and Dan puzzled over
whether this could have been the reason why the Sled was not
taking pictures for more than 7 hours on some of the last tows.
Well find
out tonight. The Night Owl Towed Camera Team worked
quickly today to replace the battery with a spare and the Sled
will go down again tonight, as planned, for Tow #7.
Todays dive included a special event. It
will be Dave Olds last dive in Alvin. Dave has been a
very valued member of the at-sea Alvin group, and one
of the key electrical techs for the sub for more than 5 years.
He took the PIT (Pilot in Training) seat and piloted the sub
expertly for the entire dive. Bruce Strickrott was the official
pilot, and Dana Yoerger was in charge of the geophysical data
collection.
While the science goes on every day, and Alvin is sent to
the seafloor to carryout experiments, the crew of RV Atlantis take
care of our floating home away from home. Today we
saw one example of how important it is to do routine maintenance
and checking of all the complex systems that keep Atlantis running.
Over the past few weeks, Chief Engineer Kevin Fisk has been monitoring
some noise made by the port aft thruster. Basically, that is the
big eggbeater or Z-drive that propels the boat forward.
Unlike many ships that use a conventional rudder
to steer, the two rear propeller thrusters on the Atlantis can
turn a full 360 degrees, allowing them to control the ships
direction instead of a rudder. Combined with the bow thruster,
which can be used to effectively push the ship
from side-to-side, Atlantis is able to finely tune its
position - very important for all of the geophysical survey work
done on board, as well as for the delicate launch and recovery
operations of deep sea vehicles like Alvin, ROV Jason
and ABE.
Kevin and his engine room crew have been keeping
track of the strange noises that the equipment has been making
and taking measurements. They found out today that they need
to keep the port thruster off, so that it does not get damaged
by further use until it can be opened up and inspected in port,
and any worn parts replaced.
This means that the ship can only go about 8 knots using the starboard
thruster.
Captain Silva spoke with the engineers and support
staff at the Marine Operations Office at Woods Hole Oceanographic
Institution and they decided that instead of heading up to San
Diego, California, where the cruise was supposed to end on February
11, we will be heading back to where we started this leg of the
journey - Manzanillo, Mexico. We hope to arrive in the middle
of the day on February 9. After letting the science party off,
the ship will continue to head North to San Diego. They expect
to arrive there on February 17.
After Alvin got on deck and the observers and pilot got out of the sphere,
the Alvin crew decided to celebrate Daves last dive by sending
him back down to the bottom... of the pool! We'll miss you, Dave! And Best of
Luck in Your Future Work!
Dive Summary
On Bottom: 0940 hours
Off Bottom: 1446 hours
Maximum Depth: 2555 meters
Todays dive continued mowing the lawn as marine geologists
and geophysicists call doing grid surveys of the type that Alvin is doing
here on the East Pacific Rise crest. Danas doppler sonar continues to
provide excellent relative navigation information and the acoustic transponder
navigation is also providing very good absolute position information. The two
data sets combined will make the interpretation of the geophysical data much
easier and help improve our ability to make geological and geophysical interpretations.
At the end of the dive they were reminded by Pat Hickey, in Top Lab, that they
had passed one of the way points where they were supposed to turn North. Dana
called up saying that they were seeing great geology, and even a large field
of extinct hydrothermal chimneys, so they decided to keep going another few hundred
meters before turning. When Dan heard this he was excited because no one had
ever found any evidence of past hydrothermal activity in this area. Tomorrow,
Dan and Del will start near the old chimneys with BLee as their pilot and carry
out the last geophysical dive of the cruise.
|